FM vs SRF vs FE vs T4 pace at Buttonwillow Raceway Park
Quickest here:T4 1:58.339 Oscar Jackson, Super Tour Feb 2025 qualifying
FMSRFFET4solid race · dashed qualifying · slower is lower
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Super Tour Feb 2026 CALCL262026-02-21
2:01.678Izzy Sanchez · fastest of 5 · top 5 within 5.9s+3.339s (+2.82%)
2:01.157Izzy Sanchez · fastest of 5 · top 5 within 7.2s+1.235s (+1.03%)
135.5Izzy Sanchez+27.2 mph (+25.1%)
25 rule changes (SRF: 3, FE: 3, T4: 19)4 cars added · 2 induction · 2 suspension & brakes · 2 tyres & wheels · 2 weight · 1 aero · 1 engine · 1 removed · 5 wording · 5 other · FE adds engine modification restrictions, testing requirements, and drivetrain violation penalties with competition suspension. · FE and FE2 Enterprise bubble tail part WM138014 now allowed; FE2 must use this configuration only. · SRF3 adds HD Oil Cooler P/N G1148500 option alongside standard P/N G480503, no fan permitted. · FE2 minimum weight stays 1270 lbs; intake manifold part number changes to WM301061; ECU to G992012; mandatory spec parts expanded; bubble tail WM138014 now FE only; SADEV transmission no modifications allowed; brake rotor part numbers to W… · SRF drivers with disabilities may modify seat and controls for safety and comfort with SCCA approval, noted in logbook, for that driver only. · SRF SADEV-SRF3 6-speed sequential transmission: effective date clarified to 1 April 2025 onward.showhide
T4 Allow Alt Bushing Material in Toe Links #39607suspension & brakes
FE FE & FE2 Rule Updates #39484wordingwordingFE adds engine modification restrictions, testing requirements, and drivetrain violation penalties with competition suspension.
T4 Alternate Placement of Fuse Panel and Electronics Request #39370other
FE FE & FE2 Bubble Tail #38978cars addedaddedFE and FE2 Enterprise bubble tail part WM138014 now allowed; FE2 must use this configuration only.
SRF Add HD Oil Cooler #38979engineadded · engineSRF3 adds HD Oil Cooler P/N G1148500 option alongside standard P/N G480503, no fan permitted.
FE FE & FE2 Rule Updates #38901wordingwordingFE2 minimum weight stays 1270 lbs; intake manifold part number changes to WM301061; ECU to G992012; mandatory spec parts expanded; bubble tail WM138014 now FE only; SADEV transmission no modifications allowed; brake rotor part numbers to W…
SRF Driver Safety & Comfort #37966otheraddedSRF drivers with disabilities may modify seat and controls for safety and comfort with SCCA approval, noted in logbook, for that driver only.
SRF Update SADEV transmission specs #37992wordingwordingSRF SADEV-SRF3 6-speed sequential transmission: effective date clarified to 1 April 2025 onward.
Super Tour Feb 2025 CALCL252025-02-22
1:58.339Oscar Jackson · fastest of 5 · top 5 within 8.3s
1:59.922Oscar Jackson · fastest of 4 · top 4 within 7.3s
108.4Tony Kiratsous
204 rule changes (SRF: 28, FE: 26, T4: 150)34 weight · 31 suspension & brakes · 21 tyres & wheels · 19 cars added · 9 engine · 8 induction · 7 aero · 2 removed · 35 wording · 38 other · FE must use SCCA Part # WM803010 Brake Line to Control Arm covers if used, as delivered, fastened with zip ties or tape only. · SRF3 air filter rule removes K&N RC-9160 option, specifies Weems P/N WM301020 only. · SRF Wilwood vented rotor minimum thickness increases to 13.25mm, 0.522 inches. · SRF3 Hoosier decal placement changed from four logos on nose and tail to three logos on sides and center front. · FE and SRF protest fee rules redirected to GCR section 8.3.1.D for fees and procedure. · FE Hoosier contingency decal requirement reduced from five decals in specific locations to three decals on sides and front. · FE and SRF protest fee rules redirected to GCR section 8.3.1.D for fees and procedure. · SRF Hoosier contingency decal requirement reduced from four decals in specific locations to three decals with simplified placement. · FE requires five Hoosier decals: one small on nose or front shock cover, one 12" on each front wing plate, one 12" on each lower floor panel before rear wheels. · SRF wet tyres: front P185/60R13 H20 or W2 and rear P205/60R13 H20 or W2 removed; front P185/65R13 W2 and rear P205/60R13 W2 now required. Hoosier decal placement specified. · FE rain light now must meet FIA Standard 8874-2019, Technical List No. 76, effective 1/1/2024. · FE allows racer's tape for crash repair, panel security, and heat exchanger opening control; seam taping banned. · SRF rain/brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24; secondary filament must connect to rain light switch. · SRF brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24, with SCCA Enterprises P/N 180427A pigtail and strobing rain light kit. · SRF adds mandatory front brake ducts 12–36 inches, throttle pedal heel-toe extension, braided stainless flex lines, camber limit 5.0 degrees, radiator opening height 3½ ± ½ inches, rear shift cable clamp P/N WM302007A. · SRF radiator options expanded: Enterprises P/N 480465 with baffle 480464, 480466, or Automotive 1R698 and CU698 allowed if cross-reference equivalent. · SRF wet front tyre changes to Hoosier P/N 46100 P185/60R13 H20 or W2 with 2.5" ground clearance. · SRF front W2 rain tyre Hoosier part number changes from 46100 to 46101 P185/65R13. · FE SADEV transmission rule removes note that all ratios under review and could be updated prior to sealing. · SRF removes 1985 Renault Alliance solid front rotor option; restrictor sizes decrease 1mm for newer Kawasaki and multi-brand engines; minimum weights increase to 1100 lbs. · FE drivers may now adjust brake bias manually during the race. · FE front and rear wing specifications clarified: adjustment ranges, shimming, Gurney flap sizes, mounting hardware, and measurement references refined. · FE engine heat shield and insulation between block and exhaust now permitted to protect fuel cell, filter, rail, lines. · FE tires must be run as delivered in sets of 4. · FE master cylinders clarified: Girling front .700" piston WM802005, rear .750" piston WM802006. · SRF tire rule wording clarified: tires must be run as delivered. · SRF brake rotor minimum thickness reduced from 13.25 mm to 12.20 mm; seals and air filter specs clarified. · SRF wet tyres front P185/65R13 W2 option added; air box clarified as-delivered; SRF3 restrictor plate G301048 mandatory Jan 1 2022; P2 motorcycle engines up to 1005cc with 35mm restrictor, 2009+ stock 1075 lbs, 2008 stock 1025 lbs, modifie… · SRF wet tyres add Hoosier W2 option alongside existing H20 from October 4, 2021. · SRF adds SADEV-SRF3 6-speed sequential transmission option with ratios 3.0–0.92:1 and 3.20 final drive. · SRF seal requirements clarified: seals now must be on driveline components in designated locations; unsealed components removed and inspected by CSR or Enterprises rather than engine shipped for testing. · FE removes qualifying tire marking requirements and rain tire set rules; renumbers tire warmer prohibition. · FE radiator screens may not protrude more than ¼ inch in front of the outside vertical plane of the sidepods. · FE radiator screens now allowed, maximum ¼ inch from sidepod front vertical plane. · SRF3 alternator pulley specified as P/N G902130 or G902130A, minimum 12oz. · SRF and SRF3 mandatory identification revised: removed Ford Performance and Blue Oval decals, added Hoosier logo placement. · FE front springs change to 800 lbs Hypercoil WM203013 Silver; rear to 900 lbs Hypercoil WM203014 Silver. · SRF rear springs limited to P/N 280390 only, previous part numbers no longer allowed; ground clearance wording clarified. · FE Gurney flaps clarified: front wing secondary only at 0.500" ±0.030", rear wing at 0.250" ±0.030". · FE Gurney flap wicker bill clarified: permitted on front wing secondary elements only, not main plane. · FE2 and FE spring part numbers WM203013 front and WM203014 rear required date moved to November 1, 2020. · SRF Penske shock P/N 280396 bump stop P/N 280407 becomes mandatory, maximum one per shock, effective 05/01/2020. · T3 BMW Z3 M & Coupe 98-99 minimum weight reduced to 3150 lbs. · FE2 Mazda 2.0L MZR engine now permitted in all SCCA events at 1250 lbs minimum; FE 2.3L becomes Regional Only through 2019 Runoffs. · T2 must have fire system installed; T3 and T4 may have one per GCR 9.3. · T3 Ford Mustang EcoBoost gains three transmission gear ratio options. · SRF rain and brake rule supersedes GCR 9.3.32.B.2 effective 1/1/2024 through 12/31/2024. · FE minimum weight rises to 1270 lbs; FE2 minimum weight rises to 1270 lbs; new spring options added; tire warmers prohibited. · SRF adds tire warmer prohibition and specifies Hoosier dry and wet tire part numbers. · SRF front nose weight minimum reduced from 35 to 32 lbs. · SRF2 becomes Regional Only; SRF3 nomenclature changed from GEN3 to Ford 1.6L conversion; SRF and SRF3 no longer compete together for points. · FE Hoosier wet rear tire width increases from 7.5 to 8.0 inches, part number 44196 W3. · T2, T3, T4 spare tire and cover removal wording clarified; removable covers now explicitly allowable to remove. · FE removes American Racer tires, mandates Hoosier dry tires 22.0 X 8.0-13 and 22.0 X 10.0-13, wet tires 22.0 X 7.5-13 and 22.0 X 9.0-13. · SRF drivers may now use Dash Windscreen Kit P/N 1180103 or P/N 180102. · FE anti-roll bar links may be removed one per end for safety, but bars must stay connected. · FE and FE2 Enterprise bubble tail P/N WM138014 newly allowed for both classes.showhide
FE Brake Line to A-Arm Covers #37110otheraddedFE must use SCCA Part # WM803010 Brake Line to Control Arm covers if used, as delivered, fastened with zip ties or tape only.
SRF Hoosier Tire Decal Placement #36739wordingwordingSRF3 Hoosier decal placement changed from four logos on nose and tail to three logos on sides and center front.
FE Protest Fee Clarification #36540wordingwordingFE and SRF protest fee rules redirected to GCR section 8.3.1.D for fees and procedure.
FE Update on Letter 36620 with new Hoosier Contingency Decal Info #36625wordingwordingFE Hoosier contingency decal requirement reduced from five decals in specific locations to three decals on sides and front.
SRF Protest Fee Clarification #36540wordingwordingFE and SRF protest fee rules redirected to GCR section 8.3.1.D for fees and procedure.
SRF Update to Letter 36619 with new Hoosier Contingency Decal Info #36624wordingwordingSRF Hoosier contingency decal requirement reduced from four decals in specific locations to three decals with simplified placement.
FE Hoosier Tire Decal Placement #36435wordingaddedFE requires five Hoosier decals: one small on nose or front shock cover, one 12" on each front wing plate, one 12" on each lower floor panel before rear wheels.
SRF Update Rain Tire Rule and Hoosier Decal Placement #36436tyres & wheelstyres & wheelsSRF wet tyres: front P185/60R13 H20 or W2 and rear P205/60R13 H20 or W2 removed; front P185/65R13 W2 and rear P205/60R13 W2 now required. Hoosier decal placement specified.
T4 T2-T4 Set expiration dates on spec lines #35378induction
FE Update FE Rain Light Rule #34707wordingwordingFE rain light now must meet FIA Standard 8874-2019, Technical List No. 76, effective 1/1/2024.
FE FE/FE2 rule update #35269wordingwordingFE allows racer's tape for crash repair, panel security, and heat exchanger opening control; seam taping banned.
SRF Update SRF Rain / Brake Rule #34706otherotherSRF rain/brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24; secondary filament must connect to rain light switch.
SRF Update SRF Brake Light Rule v1 #34853otherotherSRF brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24, with SCCA Enterprises P/N 180427A pigtail and strobing rain light kit.
T4 Ride Height Correction for the T3 Solstice. #34615suspension & brakes
T4 2002-2006 Mini Cooper S R53 Spec Line Request #34336weight -50 lbs
SRF Hoosier SRF Wet Front Tire Rule Update #34189tyres & wheelstyres & wheelsSRF wet front tyre changes to Hoosier P/N 46100 P185/60R13 H20 or W2 with 2.5" ground clearance.
T4 96-01 Audi a4 2.8 Spring Rate #34217suspension & brakes
SRF Update SRF Front W2 Rain Tire Part Number #34118tyres & wheelstyres & wheelsSRF front W2 rain tyre Hoosier part number changes from 46100 to 46101 P185/65R13.
FE Update FE SADEV Transmission Rule #33883wordingwordingFE SADEV transmission rule removes note that all ratios under review and could be updated prior to sealing.
T4 Request to Classify 2004-2008 Acura TSX in T4 #33590cars added
T4 Mazda OEM LSD was letter 32655 #32933weight -25 lbs
FE Brake bias adjuster clarification #33084suspension & brakesadded · suspension & brakesFE drivers may now adjust brake bias manually during the race.
FE FE Front and Rear Wing Update & Clarification #33089wordingwordingFE front and rear wing specifications clarified: adjustment ranges, shimming, Gurney flap sizes, mounting hardware, and measurement references refined.
T4 Another 2022 BRZ/86 T3 request #32945weight +225 lbs
FE Engine Heat Shield & Insulation #33019otheraddedFE engine heat shield and insulation between block and exhaust now permitted to protect fuel cell, filter, rail, lines.
FE Update FE/FE2 Tire Rule #32613wordingwordingFE tires must be run as delivered in sets of 4.
FE Master cylinder clarification #32669wordingwordingFE master cylinders clarified: Girling front .700" piston WM802005, rear .750" piston WM802006.
SRF SRF Tire Rule Update #32614wordingwordingSRF tire rule wording clarified: tires must be run as delivered.
SRF Brake, seal, and air filter clarifications #32670otherfasterSRF brake rotor minimum thickness reduced from 13.25 mm to 12.20 mm; seals and air filter specs clarified.
T4 Request Wider Wheels for Hyundai Tiburon #32536tyres & wheels
T4 Request to Add Spec Line for 2004-2009 Mazda3 i 2.0 #32395weight
T4 Request Alternate Front & Rear Strut/Shock Top Hats #32452suspension & brakes
T4 Request to Allow the Use of Aftermarket ECU's in Touring #31067engine
T4 Request JWT BSR Kit for 02-06 Nissan Sentra SE-R/Spec V #31685other
T4 Please Confirm Touring 4 (98-00) BMW 323 is E46 generation #31972other
T4 RX-8 Spring Part Numbers (E&O) #32151suspension & brakes
SRF SADEV-SRF3 Transmission #30926cars addedaddedSRF adds SADEV-SRF3 6-speed sequential transmission option with ratios 3.0–0.92:1 and 3.20 final drive.
SRF SRF Update Maintenance, Repairs and Seals #30961wordingwordingSRF seal requirements clarified: seals now must be on driveline components in designated locations; unsealed components removed and inspected by CSR or Enterprises rather than engine shipped for testing.
FE FE Tire Rule Changes #30754wordingwordingFE removes qualifying tire marking requirements and rain tire set rules; renumbers tire warmer prohibition.
FE Radiator Screens Clarification #30792wordingwordingFE radiator screens may not protrude more than ¼ inch in front of the outside vertical plane of the sidepods.
T4 Wrong Part Number on 320i Spec Line #30645wording
FE FE Radiator Screens #30575aeroadded · aeroFE radiator screens now allowed, maximum ¼ inch from sidepod front vertical plane.
SRF SRF3 Alternator Pulley #30684engineadded · engineSRF3 alternator pulley specified as P/N G902130 or G902130A, minimum 12oz.
T4 Civic Type R Brake Rotors #29817suspension & brakes
SRF Mandatory identification: #30223wordingwordingSRF and SRF3 mandatory identification revised: removed Ford Performance and Blue Oval decals, added Hoosier logo placement.
FE FE / FE2 Spring Updates #29689suspension & brakessuspension & brakesFE front springs change to 800 lbs Hypercoil WM203013 Silver; rear to 900 lbs Hypercoil WM203014 Silver.
SRF SRF Shocks, Springs and Ride Height. #29688otherotherSRF rear springs limited to P/N 280390 only, previous part numbers no longer allowed; ground clearance wording clarified.
T4 Request to Add a Vehicle to the Roster (contd.) #27698other
FE FE Gurney flap wicker clarification #28885wordingwordingFE Gurney flap wicker bill clarified: permitted on front wing secondary elements only, not main plane.
T4 Request to Classify 2004 Mercedes Benz 320 CLK #27663cars added
FE FE spring rule update changed to November 1, 2020 #28814wordingwordingFE2 and FE spring part numbers WM203013 front and WM203014 rear required date moved to November 1, 2020.
SRF SRF Bump Stop Correction #27019wordingwordingSRF Penske shock P/N 280396 bump stop P/N 280407 becomes mandatory, maximum one per shock, effective 05/01/2020.
T4 Request to change allowed header part # for T4 06-15 Miata #28223wording
T4 Z3M Roadster Weight #28437weightfaster · weightT3 BMW Z3 M & Coupe 98-99 minimum weight reduced to 3150 lbs.
T4 Request for 12-13 and 14-15 Honda Civic Springs #27848suspension & brakes
T4 Request to Clarify T4 05-10 Mustang Spring Allowance #27899suspension & brakes
T4 Request to Allow Brake Upgrade on T4 Mustang #27329suspension & brakes
T4 Please Switch the Solstice GXP as Specified in T2, to T3 #27413weight -50 lbs
T4 Request to Classify all Mazda RX8 Models in T3/T4 #27606cars added
FE Request for FE / FE2 preparation rules update #27722cars addedaddedFE2 Mazda 2.0L MZR engine now permitted in all SCCA events at 1250 lbs minimum; FE 2.3L becomes Regional Only through 2019 Runoffs.
T4 Clarification of On-Board Fire System for T2 #27183wordingwordingT2 must have fire system installed; T3 and T4 may have one per GCR 9.3.
T4 Mustang Ecoboost and GT Transmission #27439cars addedaddedT3 Ford Mustang EcoBoost gains three transmission gear ratio options.
T4 BRZ/FRS/86 Tire Size in T4 #27660tyres & wheels
T4 Request to add Toyota 86 GT to Spec Line #27910other
SRF SRF Rain / Brake Rule - BoD approved as follows #34958wordingwordingSRF rain and brake rule supersedes GCR 9.3.32.B.2 effective 1/1/2024 through 12/31/2024.
FE FE / FE2 Update Rules #27624weightslower · weightFE minimum weight rises to 1270 lbs; FE2 minimum weight rises to 1270 lbs; new spring options added; tire warmers prohibited.
SRF SRF Tire Warmer Rule #27622tyres & wheelstyres & wheelsSRF adds tire warmer prohibition and specifies Hoosier dry and wet tire part numbers.
SRF SRF / SRF3 Nose Weight Reduction #27706weightfaster · weightSRF front nose weight minimum reduced from 35 to 32 lbs.
SRF SRF / SRF3 Majors & Regional Class Updates #27723wordingwordingSRF2 becomes Regional Only; SRF3 nomenclature changed from GEN3 to Ford 1.6L conversion; SRF and SRF3 no longer compete together for points.
FE FE Wet Tire E&O #27365tyres & wheelstyres & wheelsFE Hoosier wet rear tire width increases from 7.5 to 8.0 inches, part number 44196 W3.
T4 Request spare tire/wheel clarification #27012wordingfasterT2, T3, T4 spare tire and cover removal wording clarified; removable covers now explicitly allowable to remove.
FE FE Tire Update #27029tyres & wheelstyres & wheelsFE removes American Racer tires, mandates Hoosier dry tires 22.0 X 8.0-13 and 22.0 X 10.0-13, wet tires 22.0 X 7.5-13 and 22.0 X 9.0-13.
SRF SRF Dash Windscreen Kit #27028aeroadded · aeroSRF drivers may now use Dash Windscreen Kit P/N 1180103 or P/N 180102.
FE FE Anti-Roll Bar Clarification #26912suspension & brakessuspension & brakesFE anti-roll bar links may be removed one per end for safety, but bars must stay connected.
FE FE / FE2 Updated Bubble Tail Rule #26913aeroadded · aeroFE and FE2 Enterprise bubble tail P/N WM138014 newly allowed for both classes.
T4 Request to allow piggy back ECU on 2000 Mazda Protégé #26085engine
T4 Request helper spring as optional #26678suspension & brakes
Super Tour Apr 2019 ST19APR262019-04-26
11 earlier rule changes on record, in force before Super Tour Apr 2019 (from 2019)3 cars added · 2 suspension & brakes · 1 engine · 1 induction · 1 tyres & wheels · 3 wording · FE Hoosier rain tyre part numbers updated: front 44195 W3, rear 44217 W3. · T4 and T3 Mazda MX-5 hardtop rules clarified: any OEM or aftermarket top permitted if retaining OEM silhouette; specific part numbers listed. · T2, T3, T4 now allow any thermostat serving original equipment intent only. · T3 and T4 Mazda MX-5 Miata eligibility capped at 2016–2018 model years. · T4 Celica GT wheelbase 2600 and 15x7 wheels added; Forte years narrowed; Fiesta ST starts 2014; Fiat 124 years 16-18 added; battery rule clarified. · T1–T4 spec car classifications clarified with permitted parts, rule conformance versions, and exclusions of other touring modifications. · T2–T4 subframe bushings now permitted to be replaced with non-spherical bushings of any material.showhide
T4 Request to classify 2000 - 2001 BMW 323 #25096cars added
FE Request to Update Hoosier Rain Tire Part Number for the FE cars #26235tyres & wheelstyres & wheelsFE Hoosier rain tyre part numbers updated: front 44195 W3, rear 44217 W3.
T4 Correct Mazda MX-5 Hard Top Notes #26137wordingwordingT4 and T3 Mazda MX-5 hardtop rules clarified: any OEM or aftermarket top permitted if retaining OEM silhouette; specific part numbers listed.
T4 Consider opening class rules to allow any thermostat #26187engineadded · engineT2, T3, T4 now allow any thermostat serving original equipment intent only.
T4 Cap 2016 Mazda Miata year at 2018 #26388cars addedremoved · cars addedT3 and T4 Mazda MX-5 Miata eligibility capped at 2016–2018 model years.
T4 2012-2015 Honda Civic Si Performance Request #26129suspension & brakes
T4 Errors, Omissions, and Updates (Various) #22414wordingwordingT4 Celica GT wheelbase 2600 and 15x7 wheels added; Forte years narrowed; Fiesta ST starts 2014; Fiat 124 years 16-18 added; battery rule clarified.
T4 Request for Adjustments to fiat 124 specline #25371induction
T4 Add Clarification to Spec Car Classifications Vehicle Spec #25774wordingwordingT1–T4 spec car classifications clarified with permitted parts, rule conformance versions, and exclusions of other touring modifications.
T4 Clarify Subframe Bushings Permitted for T2-T4 #25800suspension & brakesadded · suspension & brakesT2–T4 subframe bushings now permitted to be replaced with non-spherical bushings of any material.
T4 Consider Solo SSC cross over classification into T4 #25802cars added
About this data
Best is the class's fastest lap in that event's qualifying or race sessions, with the driver who set it, how many cars set a time that session and how close the top five were; a best from fewer than three cars is greyed. With two or more classes, "vs" is the gap of each class's best to the first class's at the same event. "% of FM" is the class's best as a share of FM's best at the same event (100% is level, less is quicker): weather and track condition move every class together, so this compares across years where the raw times do not. It still breaks when FM's own field changes or one session was wet and another dry. Newest event first. The coloured figure under each value is the change from the previous event that has one (green is quicker, red slower). Whole laps only, so events with different sector layouts still compare. Weather and track condition are not accounted for.